1939 results about "Ascorbic acid" patented technology

Provided are a whitening and freckle-removing composition, a gel, a preparation method therefor, and a use thereof, relating to the technical field of skin-care products. The whitening and freckle-removing composition comprises tranexamic acid, nicotinamide, 4-butylresorcinol, licorice extract, 3-o-ethyl ascorbic acid, and glutathione. For the whitening composition, by inhibiting the activity of tyrosinase, blocking the transfer of melanin from melanocytes to keratinocytes, and inhibiting the formation and accumulation of melanin by means of multiple mechanisms including oxidation resistance, and by means of the synergistic action of all components, cosmetic benefits of whitening and freckle-removing are achieved. The whitening and freckle-removing gel has a simple preparation method, has a mild and non-sensitizing formula, is safe and non-irritating, and is suitable for large-scale production and application.

The invention discloses a seed priming method for improving early-stage disease resistance of pepper seeds, which belongs to the field of agricultural planting and comprises the following steps: S1, pre-cleaning: soaking the seeds with sodium hypochlorite and then cleaning the seeds with sterile deionized water; s2, pulse phosphorylation activation treatment: adding seeds and an activation solution into a pressure-resistant polypropylene container connected with a vacuum pipeline, sealing, vacuumizing to-0.08 MPa, maintaining for 5-10 minutes, then recovering to normal pressure, transferring to a constant-temperature oscillator, and carrying out phosphorylation activation treatment; s3, immune training treatment: transferring the seeds subjected to phosphorylation activation treatment to an initiation solution containing UV-inactivated phytophthora capsici spore suspension and H2O2, and carrying out intermittent ventilation treatment; s4, stabilizing treatment: transferring the seeds subjected to immune training treatment into an ascorbic acid solution for treatment, filtering, and drying in the shade to obtain the pepper seeds. According to the invention, the problem of immune response interruption caused by insufficient signal intensity and fast protein turnover when a simulated environment is used for excitation in the prior art is solved.

The invention relates to the technical field of total phosphorus detection, in particular to a method for determining total phosphorus in water, which comprises the following steps: 1) digestion treatment: adding an oxidant into a water sample to be detected, and then performing microwave digestion treatment to obtain digested water; a molybdate reagent is added into the digested water, then an improved ascorbic acid solution is added, a chromogenic reaction is completed at the set temperature, and the improved ascorbic acid solution is obtained by mixing an ascorbic acid solution and sodium ethylene diamine tetracetate; measuring the concentration: measuring the absorbance value of the obtained color development product by using a spectrophotometer and a long-optical-path cuvette; and drawing a standard curve: using a phosphorus standard solution as a quality control sample, adding a plurality of calibration points in a low-concentration interval of 0.0-0.1 mg / L, carrying out colorimetric determination, and establishing quadratic equation fitting according to absorbance and concentration so as to determine the total phosphorus content of the water sample to be detected, and the method has the advantages of high sensitivity and good accuracy in total phosphorus testing.

The invention belongs to the technical field of rare and precious metal recovery, and particularly relates to a method for recovering metallic silver from waste crystalline silicon battery pieces, which comprises the following steps: (1) putting the waste crystalline silicon battery pieces into an inorganic alkali aqueous solution for soaking reaction to obtain an aluminum-containing solution and dealuminized crystalline silicon pieces; (2) adding the dealuminized crystal silicon wafer into a mixed solution of organic acid and hydrogen peroxide for soaking reaction, filtering and washing to respectively obtain silver-containing filtrate and a silver-removed silicon wafer; (3) carrying out chlorination precipitation reaction on the silver-containing filtrate and a chlorine source, filtering and drying to obtain silver chloride powder; (4) adding silver chloride powder into an ammonia water solution, heating and stirring to completely dissolve silver chloride to obtain a silver-ammonia solution; (5) adding PVP (Polyvinyl Pyrrolidone) into the silver-ammonia solution, heating and stirring until the PVP is completely dissolved, adding ascorbic acid, and carrying out reduction reaction at room temperature to obtain metal silver powder precipitate; and filtering, washing and drying the precipitate to obtain the spherical silver powder. According to the method, the silver recovery efficiency is high, the spherical nanoscale silver powder can be prepared, and the purity is high.

The invention discloses a cyclic peptide compound as well as a preparation method and application thereof, belongs to the field of polypeptide synthesis and application, and particularly relates to full-protection peptide resin prepared by solid-phase synthesis. Carrying out cutting and monocyclization on the full-protection peptide resin to obtain monocyclic peptide; the monocyclic peptide is subjected to binary cyclization treatment to obtain a cyclic peptide compound Cyclo (His-Lys-Cys-Gly-His-Lys-Cys-Gly-, and a disulfide bond is in bridge connection with Cysamp; and the binary cyclization is cyclized under the action of iodine methanol and ascorbic acid. The cyclopeptide compound prepared by the invention has the advantages of low toxicity, good stability, good antioxidant effect and good anti-inflammatory effect, and the expression of type I collagen can be improved. Therefore, the invention has the advantages of low toxicity, good stability, good antioxidant effect and good anti-inflammatory effect, and can improve the expression of the type I collagen.

The invention belongs to the technical field of catalyst preparation, focuses on a high-entropy alloy nanowire catalyst, and mainly relates to a preparation method and application of an AuCuAgPtNi catalyst. A one-pot wet chemical method is innovatively adopted, a 4-aminopyridine solvent and metal precursors of gold, copper, silver, platinum and nickel are fully and evenly mixed and placed in an oil bath pot at the temperature of 90 DEG C, then a reducing agent ascorbic acid is rapidly added, after specific reaction time, washing, drying and other operations are sequentially carried out, and the high-entropy alloy nanowire AuCuAgPtNi catalyst can be successfully prepared. The preparation method disclosed by the invention has the remarkable advantages of simple process, simple steps, convenience in operation and the like. In an alkaline environment, the prepared nanowire-shaped high-entropy alloy AuCuAgPtNi catalyst shows extremely excellent catalytic activity and selectivity for catalytic degradation of waste plastic polylactic acid, the waste plastic can be efficiently upgraded and converted into pyruvic acid, a new way is opened up for resource utilization of the waste plastic, and the application prospect is wide. The method has a wide application prospect in the fields of environmental protection and resource recovery.

The invention belongs to the technical field of battery materials, and particularly discloses preparation and application of a strontium lanthanum manganate-coated lithium ferric manganese phosphate composite material, and the method comprises the following steps: firstly, preparing strontium lanthanum manganate by adopting a lanthanum source, a strontium source and a manganese source as raw materials; respectively adding a lithium source, a phase transfer agent, a phosphorus source, L-ascorbic acid, an iron source and a manganese source into a solvent, and preparing a lithium ferric manganese phosphate precursor by using a solvothermal method; the lithium ferric manganese phosphate material is coated twice through strontium lanthanum manganate and carbon. According to the invention, strontium lanthanum manganate is used as a coating material, and the addition of lanthanide elements improves the crystal stability of lithium ferric manganese phosphate, keeps the integrity of an olivine-type structure, and avoids capacity fading caused by structure collapse, thereby improving the cycle stability of the lithium ion battery.

The invention belongs to the technical field of stainless steel surface treatment, and particularly relates to a stainless steel passivation solution and a preparation method thereof. The water-based cutting fluid is prepared from the following raw materials: cerium salt, copper sulfate, citric acid, sodium dihydrogen phosphate, ammonium molybdate, sodium tungstate, aminated-silane modified SiO2 nanoparticles, polyethylene glycol, L-ascorbic acid, polyaspartic acid, an anti-settling agent, a surfactant and the balance of deionized water. According to the invention, a three-dimensional network skeleton is constructed by using aminated-epoxy group silane modified SiO2 nanoparticles, so that the problem of weak interface bonding force of a traditional passivation layer is solved; according to the formula, the proportion of biodegradable components such as citric acid and polyaspartic acid is extremely high, cerate adopts a low-toxicity rare earth compound, molybdenum / tungsten elements are fixed in a stable oxide form, the dosage of EDTA is remarkably reduced through a compounding technology, residual ions are adsorbed in combination with a three-dimensional network, and the balance of environment friendliness and long-acting corrosion resistance is achieved.

The invention relates to the field of foaming materials, in particular to a low-solvent-residue expandable polystyrene material and a preparation method thereof. The expandable polystyrene material with low solvent residue comprises the following raw materials in percentage by weight: 0.35-0.45% of a free radical initiation system, 0.35-0.45% of S, S, S, S, S, S, S, S, S, S, S, S, S, S, S According to the present invention, the material comprises, by weight, 0.1-0.15% of S, S '-bis (alpha, alpha'-dimethyl-alpha ''-acetoxy) trithiocarbonate, 0.15-0.2% of ascorbic acid, 0.1-0.2% of a nucleating agent, 0.2-0.3% of a suspending agent, 0.001-0.003% of an emulsifier, 5-6% of a foaming agent, 0.15-0.25% of a plasticizer, 0.001-0.002% of hydroxyethyl cellulose, 0.05% of sodium phosphate, 0.1-0.2% of zinc stearate, and 0.1-0.2% of glyceryl stearate, the obtained material has low solvent residue, meets food safety requirements, and is suitable for food packaging.

The invention relates to the technical field of zinc glycinate production, and provides a zinc glycinate chelate preparation method, which comprises: (1) pre-mixing glycine and nano zinc oxide, adding into water, and carrying out microwave treatment and ultrasonic-assisted synergistic treatment to prepare a glycine suspension; (2) adding L-ascorbic acid, stirring, maintaining the temperature at 58-62 DEG C for 30-40 minutes, heating to 74-80 DEG C, and maintaining the temperature at 74-80 DEG C for 2-3 hours; and (3) cooling to room temperature, standing, centrifugally separating, and drying to obtain the zinc glycinate chelate. According to the preparation method of the glycine zinc chelate, the production cost is effectively reduced and the production efficiency is improved under the condition that the purity and the stability of the product are ensured.

A fracturing fluid for fracturing subterranean formations comprising ascorbic acid. The fracturing fluid can use ascorbic acid to delay increases in viscosity until desired. The viscosity increase can then be maintained over a period of time to perform fracturing operations.

The present invention discloses a method for preparing highly dispersible submicron spherical palladium powder. The method comprises the following steps: first, weighing solid palladium nitrate and dissolving it in dilute nitric acid to prepare a dilute palladium nitrate solution; then dissolving a reducing agent in deionized water to obtain a reducing solution; then weighing a dispersant and an additive and dissolving them in deionized water to obtain a mixed base solution; and then mixing the three to obtain a reaction slurry containing palladium powder. The mixture is then filtered, washed, and dried to obtain submicron spherical palladium powder particles. The present invention adopts a liquid phase reduction method to reduce the palladium nitrate solution with ascorbic acid or hydrazine hydrate as a reducing agent to prepare the submicron spherical palladium powder. An organic polymer dispersant and a small molecule alcohol additive are simultaneously added to the base solution in a symmetrical manner. While ensuring the yield of palladium powder, the particle growth process and dispersibility are well controlled. The prepared palladium powder particles are spherical and highly dispersed, with a particle size of 100 to 600 nm.

The invention belongs to the field of synthesis of nano materials, and particularly relates to a core-shell structure gold nano star and a preparation method and application thereof, and the core-shell structure gold nano star comprises a first gold nano star containing a metal sulfide shell layer and a second gold nano star containing a metal oxide shell layer. The preparation method comprises the following steps: firstly preparing a gold nano star core solution, and then respectively adding different precursors to prepare two core-shell structure gold nano stars. The method has the advantages of simple synthesis conditions and non-toxic reagents. The core-shell structure gold nanostars are used for preparing a detection solution based on a buffer solution, a color developing agent and an oxidizing agent, the detection solution reacts with antioxidants, a data matrix is constructed by measuring absorbance changes and is analyzed, single, binary and ternary combinations of various antioxidants such as ascorbic acid and glutathione can be accurately distinguished, and the detection accuracy is improved. The application prospect in the fields of biomolecules and food detection is good.

The invention provides a preparation method and application of red nano-selenium particles, and relates to the technical field of nano-medicines.The preparation method comprises the steps that sodium selenite is dissolved in ultrapure water, silicate microspheres containing copper, zinc and aluminum are added, the pH value is 4.8, 1.5 M of ascorbic acid solution is dropwise added while stirring, the temperature is increased till solid ascorbic acid is added, the pH value is adjusted through NaOH, and nano-selenium suspension liquid is obtained through stirring reaction; the preparation method comprises the following steps: mixing and stirring a nano-selenium suspension, a sodium alginate sulfydryl graphene oxide mixture and a chitosan oligosaccharide citric acid buffer solution, centrifugally washing, and freeze-drying to obtain red nano-selenium particles, and preparing the copper-zinc-containing aluminosilicate microspheres through mesoporous template calcination and copper-zinc co-doping. The red nano-selenium particles prepared by the method have a core-shell structure, uniform particle size, high oxidation resistance and remarkable interface bonding strength.

The invention discloses a synthesis process of vitamin C ethyl ether, and belongs to the technical field of vitamin C derivative synthesis. The process comprises the following steps: taking L-ascorbic acid as a raw material, adding acetone, anhydrous cupric sulfate and acetyl chloride, and reacting for 1-2 hours at 38-40 DEG C under the protection of nitrogen to obtain a vitamin C protector; adding alkali, water, an alkylating reagent and absolute ethyl alcohol into the reaction product, reacting for 3 hours at 75-78 DEG C under the protection of nitrogen, and performing reduced pressure distillation to obtain a vitamin C protector etherate; and finally, hydrolyzing by using cationic resin, removing a protecting group, and recrystallizing by using ethyl acetate to obtain the vitamin C ethyl ether. Through the synergistic catalysis of anhydrous cupric sulfate and acetyl chloride, the reaction time is remarkably shortened, and the product purity and yield are improved. Through detection, the product purity is more than 99.5%, the total yield can reach more than 80%, and an efficient and economical method is provided for industrial production of vitamin C ethyl ether.

The invention relates to the technical field of bacterium enrichment nutrient solutions, in particular to a bacterium enrichment nutrient solution for fermentation and a preparation method of the bacterium enrichment nutrient solution. The culture medium is prepared from the following raw materials in parts by weight: maltodextrin, crystalline glucose, low-pigment yeast extract powder, refined soy peptone, dipotassium phosphate, monopotassium phosphate, magnesium sulfate heptahydrate, sodium chloride, phytic acid, L-ascorbic acid, manganese sulfate monohydrate, biotin, thiamine hydrochloride and choline chloride. Through a double-carbon-source structure, maltodextrin and crystalline glucose cooperate, metabolic oscillation is avoided, and the energy utilization rate is increased; the low-pigment yeast extract powder and the refined soy peptone are complementary, so that the rapid growth requirement of thalli is met; phytic acid is chelated with metal ions to prevent precipitation, L-ascorbic acid is used for resisting oxidation, and biotin and thiamine activate a coenzyme pathway to realize accurate regulation and control of a metabolic network.

The invention belongs to the technical field of bioengineering, and particularly relates to a sucrose phosphorylase mutant and application thereof in synthesis of 2-O-alpha-D-glucopyranosyl-L-ascorbic acid. The sucrose phosphorylase mutant is obtained by simultaneously mutating multiple sites of amino acids at the 91st site, the 154th site, the 185th site, the 323rd site and the 424th site of wild sucrose phosphorylase derived from Bifidobacterium pseudolongum, so that the efficiency of producing 2-O-alpha-D-glucopyranosyl-L-ascorbic acid by taking sucrose and vitamin C as raw materials is remarkably improved; only 15 hours are needed for completely catalyzing 1.2 M of vitamin C to produce 2-O-alpha-D-glucopyranosyl-L-ascorbic acid; and the yield of the 2-O-alpha-D-glucopyranosyl-L-ascorbic acid reaches 358 g / L. Therefore, the 2-O-alpha-D-glucopyranosyl-L-ascorbic acid has an important application value in the field of production of the 2-O-alpha-D-

The invention belongs to the technical field of preparation of biological materials, and particularly discloses a sea cucumber flower self-assembled polypeptide-iron nano-carrier as well as a preparation method and application of the sea cucumber flower self-assembled polypeptide-iron nano-carrier. The preparation method comprises the following steps: dissolving freeze-dried sea cucumber flower powder in deionized water, adjusting the pH value to be alkaline, heating and stirring, centrifuging, discarding the precipitate, adjusting the pH value to be acidic, centrifuging, collecting the precipitate, and freeze-drying to obtain sea cucumber flower protein powder; preparing a reaction solution, adding simulated gastric juice and simulated intestinal juice, stirring for reaction, inactivating protease, centrifuging, taking supernatant, and freeze-drying to obtain sea cucumber flower self-assembled polypeptide; the preparation method comprises the following steps: preparing a solution from sea cucumber, adding FeCl2. 4H2O and ascorbic acid, adjusting the pH value to be acidic, carrying out heating reaction, centrifuging, discarding the supernatant, and freeze-drying to obtain the sea cucumber flower self-assembled polypeptide-iron nano-carrier. The invention discloses a sea cucumber flower self-assembled polypeptide-iron nano-carrier as well as a preparation method and application thereof. The carrier can promote absorption of an organism to iron, a relatively high iron ion release rate is maintained in an intestinal environment, and the in-vivo bioavailability of iron ions is improved.

The invention provides high-performance silver powder suitable for TOPCon battery fine grid silver paste, a preparation method of the high-performance silver powder and the silver paste, and belongs to the technical field of photovoltaic materials. The preparation method comprises the steps that a silver salt solution and a composite reducing agent are mixed, a first-stage hydrothermal reaction is carried out at the first temperature, a second-stage hydrothermal reaction is carried out at the second temperature, and silver powder is obtained after centrifugation, washing and drying; wherein the composite reducing agent is selected from a mixture of two of potassium tartrate, sodium sulfite and ferrous sulfate. According to the method, gradual growth and crystallinity improvement of silver crystal nucleuses are achieved through two-stage heating, particle aggregation or uneven morphology caused by rapid reduction is avoided, in addition, the adopted composite reducing agent combination is remarkably superior to a single reducing agent (such as ascorbic acid), and the morphology and particle size distribution of the silver powder can be more accurately regulated and controlled.

The invention belongs to the technical field of hepatopathy treatment drugs, and particularly relates to an anti-inflammatory and anti-oxidative stress nano-enzyme Cu5.4O atCNDs with cascade enzyme activity and application of the nano-enzyme Cu5.4O atCNDs. The nano-enzyme Cu5.4O-coated CNDs is prepared by the following steps: dissolving CuCl2 in a carbon dot aqueous solution, reacting for 10-12 minutes at the temperature of 75-80 DEG C, then adding an L-ascorbic acid aqueous solution, regulating the pH value to 7.0-8.0 by using a NaOH solution, reacting for 10-12 hours at the temperature of 75-80 DEG C, after the reaction is finished, centrifuging to remove precipitates, dialyzing supernate, and freeze-drying to obtain the Cu5.4O-coated CNDs. Research results of the invention prove that the nano-enzyme Cu5.4O-coated CNDs has the potential of treating various acute liver injury diseases, and is an intervention strategy with a good clinical application prospect.

The invention discloses a super-retarding type polycarboxylic acid water reducing agent and a preparation method and application thereof, and belongs to the field of concrete water reducing agents. The preparation method comprises the following steps: taking acrylic acid AA, isobutenol polyoxyethylene ether HPEG and hydroxyethyl acrylate HEA as monomers, taking mercaptopropionic acid MPA as a chain transfer agent, taking hydrogen peroxide H2O2 and L-ascorbic acid Vc, and mixing in proportion to serve as an initiator; preparing a first and second monomer mixed solution; adding bottom water into the reaction kettle, and carrying out stepwise polymerization reaction; and cooling the reaction liquid, adjusting the pH value, filtering, and discharging to obtain the product. According to the invention, an ester functional monomer hydroxyethyl acrylate HEA is introduced, and a step-by-step polymerization technology is adopted to control the dispersion process of water reducing agent molecules on cement particles, so that the water reducing agent molecules continuously disperse the cement particles within a certain period of time; the problem that the slump loss is too fast due to long-time and long-distance transportation of concrete or transportation in high-temperature weather is effectively relieved.

The invention discloses a resource utilization method of Fenton iron mud. According to the method, a citric acid-ascorbic acid composite solution is used for soaking Fenton iron mud, hydrothermal liquefaction is carried out in an inert reduction system, ferric iron is reduced into ferrous iron, and a ferrous iron solution generated after reaction can directly form a Fenton reagent with hydrogen peroxide to be reused for Fenton reaction. By the adoption of the method, iron can be completely recycled, resource utilization of the Fenton iron mud is facilitated, the mass of the treated filter residues is only 1 / 10 of that of the iron mud, and the disposal amount of hazardous waste is effectively reduced.

The invention provides a recombinant III-type humanized collagen gel based on a macromolecular crowding effect as well as a preparation method and application of the recombinant III-type humanized collagen gel. The method comprises the following steps: firstly, preparing an rhCol III solution system; then preparing a macromolecular crowding bath containing dextran 70, polyethylene glycol 8000 and ascorbic acid; then adding an rhCol III solution into the macromolecular crowding bath to form an rhCol III microgel; and finally, constructing a 3D printing molecular exclusion mold system which takes agarose as a substrate and contains a functional additive and a temperature-sensitive polymer as a temperature-sensitive release and spatial constraint component, so as to realize directional construction of the rhCol III microgel. According to the method disclosed by the invention, second-level physical gelling (lt; 15s) of rhCol is realized, and a physiological microenvironment supporting cell proliferation is constructed. The recombinant III-type humanized collagen gel prepared by the method can be used for preparing collagen microgel balls, collagen bundles, 3D (three-dimensional) bio-printing products and the like, and is wide in application range.

The invention belongs to the technical field of lithium ion battery material recovery, and discloses a regeneration, repair and doping method of a waste lithium iron phosphate material and a regenerated positive electrode material. The method comprises the following steps: firstly, immersing waste LiFePO4 powder into a mixed solution of citric acid and ascorbic acid, oscillating to selectively dissolve out Fe < 3 + > impurities, and synchronously reducing Fe < 3 + > on the surface to Fe < 2 + >; then Li2CO3 is added into the leached powder for lithium bit compensation, and ball milling and uniform mixing are carried out; then Al2O3 and TiCl3 are added for aluminum-titanium co-doping, and ultrasonic dispersion is carried out uniformly; and finally, carrying out segmented sintering. In the first stage, sintering is carried out in an air atmosphere at 300-350 DEG C; in the second stage, sintering is performed at 600-700 DEG C in an inert gas atmosphere; and finally obtaining the regenerated positive electrode material. According to the method, waste lithium iron phosphate batteries can be turned into wealth, the lithium iron phosphate positive electrode material with good electrochemical performance is obtained, the complex and expensive impurity removal process is omitted, the cost is low, and possibility is provided for large-scale industrial regeneration and repair of waste lithium iron phosphate active substances.

The invention provides a new energy automobile battery flexible disassembling adhesive and a preparation method thereof, and belongs to the technical field of new energy automobile batteries, the flexible disassembling adhesive comprises the following components by weight: 45-50 parts of deionized water; 8 to 10 parts of gamma-butyrolactone; 5 to 8 parts of propylene glycol methyl ether acetate; 2 to 3 parts of microencapsulated lipase; 2 to 3 parts of nano cellulose immobilized protease; 6 to 8 parts of urea peroxide; 0.5 to 1 part of nano manganese dioxide; 0.7 to 1.1 parts of a sodium citrate / sodium lactate buffer solution; 1.5 to 2.5 parts of polyvinylpyrrolidone K30; 0.8 to 1.2 parts of hydroxypropyl methyl cellulose; 0.05 to 0.1 part of a graphene oxide nanosheet; 0.5 to 0.8 part of a benzotriazole derivative; 0.1 to 0.3 part of sodium molybdate; 6 to 8 parts of sorbitol; and 5-7 parts of ascorbic acid. The flexible disassembly adhesive solves the problems of low efficiency, serious environmental pollution, high safety risk and low material recovery rate in traditional battery disassembly.

The invention discloses an anti-aging and anti-oxidation bicyclic peptide compound as well as a preparation method and application thereof, belongs to the technical field of polypeptide compound synthesis, and particularly relates to full-protection peptide resin prepared by solid-phase synthesis. Carrying out cutting and unitary cyclization on the full-protection peptide resin to obtain unitary cyclic peptide; carrying out binary cyclization treatment on the unitary cyclic peptide to obtain a bicyclic peptide compound Cyclo (His-Cys-Lys-Gly-His-Cys-Lys-Gly-, and bridging a disulfide bond with Cysamp; the binary cyclization comprises cyclization under the action of iodo methanol and ascorbic acid; or the binary cyclization is cyclized in DMSO (Dimethylsulfoxide). The anti-aging and anti-oxidation bicyclic peptide compound prepared by the preparation method disclosed by the invention has the following beneficial effects of low toxicity, good stability, capability of improving I-type collagen expression, good anti-oxidation effect and good anti-inflammatory effect.

The invention relates to the technical field of electro-catalysis materials, and discloses an iron-doped copper oxide catalyst, a preparation method thereof and application of the iron-doped copper oxide catalyst in electro-catalysis of nitrate to synthesize ammonia. The method comprises the steps that CuCl2 serves as a metal precursor, ascorbic acid serves as a reducing agent, and Cu2O nanoparticles are obtained through a hydrothermal precipitation method; then, Cu2O is added into a solution containing FeSO4, sodium borohydride is added, centrifugal washing and drying are carried out, and the iron-doped copper oxide nitrate electroreduction catalyst which is rich in defects and uniform in metal dispersion is obtained through a programmed heating pyrolysis reduction method. The electro-catalytic material obtained by adopting the method disclosed by the invention has a relatively large catalytic active area and relatively abundant defect sites and oxygen vacancies, the nitrate adsorption and activation effects are improved, the supply of active hydrogen is promoted by constructing stable heterogeneous active sites, the product selectivity and Faraday efficiency in NO3RR are improved, and the electro-catalytic material has good durability.

The invention discloses a europium-based metal-organic framework as well as a preparation method and application thereof, and belongs to the technical field of bioassay materials. The preparation method of the europium-based metal-organic framework comprises the following steps: adding europium salt, H4BTA-2OH and ascorbic acid into a binary solution, and sequentially performing ultrasonic treatment, heating and post-treatment to prepare the europium-based metal-organic framework (the molecular formula is {[(CH3) 2NH2] [Eu (BTA-2OH) (H2O) 2]. 4H2O} n). In addition, the invention also discloses an application of the europium-based metal-organic framework in detection of a bacillus anthracis biomarker 2, 6-dipicolinic acid (DPA). The europium-based metal-organic framework Eu-MOF prepared by the method can rapidly detect 2, 6-dipicolinic acid, and has high selectivity and sensitivity, and the excellent fluorescence sensing ability means that the europium-based metal-organic framework Eu-MOF is a potential bacillus anthracis detection material.

The present invention relates to the technical field of daily chemical technology, and specifically provides a whitening and freckle-removing cream. The freckle-removing cream comprises the following components in parts by weight: water, glycerin, mineral oil, antioxidant microcapsules, polydimethylsiloxane, sodium ascorbyl phosphate, niacinamide, a plant compound extract, essence, and cetearyl alcohol. The present invention adds natural plant extract ingredients, which is safe and effective. A circulation device is used to promote the effective combination of active ingredients, so that the active ingredients can quickly penetrate into the inner layer of the skin, thereby improving the transdermal absorption ability of the active ingredients. A unique encapsulation technology is used to firmly adhere the active ingredients to the skin surface, thereby effectively lightening facial spots, removing dullness from the skin, and restoring luster.

The invention provides a GelMA microneedle patch loaded with chromogenic gold nano bipyramids and a preparation method thereof.The method comprises the steps that citric acid, chloroauric acid and a CTAC solution are mixed, then sodium borohydride is added, and a seed solution is obtained through stirring and standing; mixing chloroauric acid, silver nitrate, hydrochloric acid and CTAB (cetyltrimethyl ammonium bromide), and sequentially adding ascorbic acid and the seed solution to obtain a growth solution; carrying out centrifugation, morphology regulation and chemical etching purification to obtain a chromogenic gold nano bipyramid solution; the preparation method comprises the following steps: reacting gelatin with methacrylic anhydride in PBS, dialyzing and freeze-drying to obtain GelMA; dissolving GelMA in the gold nanoparticle bipyramid solution, and adding a photoinitiator LAP to obtain a mixed precursor solution; and the GelMA microneedle patch loaded with the gold nano bipyramid is prepared through mold casting, centrifugation, ultraviolet light crosslinking and drying demolding. The microneedle extraction and gold nano bipyramid color development integrated scheme is initiated, blood sampling is not needed, the dermis interstitial fluid is extracted in a minimally invasive mode through the microneedle, detection pain and trauma are reduced, the cross infection risk of blood treatment is avoided, and the microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle